We were working in the middle of a local elementary school field when my partner notices this shiny craft high in the morning sky.It was a shiny glowing silver cylinder.We watched this craft travel on a straight path from horizon to horizon.It only made a jet like sound when it was over head for about 10 seconds.The sound started suddenly and ended suddenly.It did not produce a vapor trail.It was on the flight path from Alaska to Bangor Washington. We often see the U.S.fighters traveling this path from base to base to base and they are easy to identify.This cylinder had no identifying marks.Could this be a new Air Forse spy plane? Is it possible to let me know if anybody else knows anything about these cylinders.